Send .NET application data to Observe¶

Compatibility¶

.NET 4.6.2+ on the following platforms:

x86
AMD64 (x86-64)
ARM64 (Experimental, CentOS images not supported)

Get the Observe Agent¶

Install the Observe agent in your environment.

Install the OpenTelemetry zero-code instrumentation for .NET¶

The instrumentation is distributed via an installer script.

Linux

# Download the bash script
curl -sSfL https://github.com/open-telemetry/opentelemetry-dotnet-instrumentation/releases/latest/download/otel-dotnet-auto-install.sh -O

# Install core files
sh ./otel-dotnet-auto-install.sh

# Enable execution for the instrumentation script
chmod +x $HOME/.otel-dotnet-auto/instrument.sh

# Setup the instrumentation for the current shell session
. $HOME/.otel-dotnet-auto/instrument.sh

Mac OS

coreutils is required. You can install it with:

brew install coreutils

From here the instructions are the same as for Linux.

Windows

Run the following as an administrator in Powershell 5.1+:

# Download the module
$module_url = "https://github.com/open-telemetry/opentelemetry-dotnet-instrumentation/releases/latest/download/OpenTelemetry.DotNet.Auto.psm1"
$download_path = Join-Path $env:temp "OpenTelemetry.DotNet.Auto.psm1"
Invoke-WebRequest -Uri $module_url -OutFile $download_path -UseBasicParsing

# Import the module to use its functions
Import-Module $download_path

# Install core files (online vs offline method)
Install-OpenTelemetryCore

Instrument an ASP.NET application deployed on IIS¶

Run the following in Powershell (note, the final command will cause IIS to restart):

Import-Module "OpenTelemetry.DotNet.Auto.psm1"

Install-OpenTelemetryCore

Register-OpenTelemetryForIIS

Configure the instrumentation¶

Set the following environment variables:

Environment variable	Value
`OTEL_SERVICE_NAME`	your service name

Run your instrumented app¶

Linux/Mac OS

./MyNetApp

Windows

.\MyNetApp.exe

Next steps¶

Troubleshooting¶

If your data is not showing up in Observe, first verify that Observe Agent is receiving data from your application. See Troubleshooting the Observe Agent.

Common reasons why the Observe agent is not receiving traces from your application:

Default exporter settings override¶

By default, OpenTelemetry instrumentation exports data using standard OTLP settings, which are automatically compatible with the Observe Agent’s default receiver configuration.

This means that data from your application might not be reaching the Observe Agent if you have overridden the following environment variables with non-default settings:

OTEL_EXPORTER_OTLP_ENDPOINT
OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
OTEL_EXPORTER_OTLP_LOGS_ENDPOINT

Ensure these variables are unset or set to the correct endpoint (e.g., http://localhost:4317 for gRPC or http://localhost:4318 for HTTP).

Ports blocked by firewall¶

Ensure that any firewalls within the same network as your app and collector are configured to allow traffic on ports 4317 and 4318. The application instrumentation uses these ports to communicate with the Observe agent.